Todd and Ula Nelkin of Houston have been trying to have a baby for several years. When they were unable to conceive naturally, they turned to IVF, but suffered two failed attempts.

The first attempt resulted in an ectopic pregnancy, which is when the pregnancy occurs outside the womb and the fetus cannot survive.

"I can still picture my wife breaking down crying when my doctor said, 'I'm sorry, there's not a heartbeat,'" Todd Nelkin, 44, said. "I work as hard as I can every day to make sure that she doesn't cry and to have her break down like that in front of me is one of the most scarring images of my life."

He and wife, 42, own a sports-memorabilia shop in Houston.

The second IVF failed at the get-go. The couple have now decided that they want to try IVF one more time before exploring the option of adoption, but they need some financial help for the costly procedure.

"We have a house payment, car payment, loan payment like everyone else and you reach a point where you say, 'OK, what are our other alternatives?' and having a card like this is a pretty amazing backdrop," Todd Nelkin said. "It's something to fall back on. We're hoping the right person sees the auction."

The item to which Nelkin refers is a one-of-a-kind card, double autographed by legendary running backs Barry Sanders and the late Walter Payton.

"This card is the only one of the 100 made to be graded a perfect 10 and I would like to think that maybe this could be the only card in the history of the world that could be responsible for a human life existing and that's a nice addition to the card," Nelkin said.

Experts have told Nelkin that the card could be worth up to $20,000.

"As far as I'm concerned, the winning bidder could make the check to Baylor College of Medicine," he said. "The money is going straight to the hospital. That's the only goal of this whole auction."

The Nelkins' story caught the attention of NFL Hall of Famer Sanders himself. The former Detroit Lions running back tweeted Todd Nelkin to voice his support.

In a statement to ABC News' Houston affiliate KTRK-TV, Sanders said, "I want the Nelkins to know that I am supportive in helping spread the word about their cause and since this one-of-a-kind item cannot be replaced, I wanted to send them another signed card to have in its place."

Nelkin said it was "pretty unreal" when he saw Sanders' message.

"It's not every day a Heisman trophy-winner text messages you," he said. "You don't think that people like that know about people like me."

Nelkin knows that the last IVF attempt does not guarantee a child for the couple, but he dreams of the day when he will be a father.

"I'm hoping we get a little person that talks too much on the phone, talks back to me, puts a dent in the car where there shouldn't be one," he said. "I'm sure there will come a time to where we're standing in the front yard saying, 'Honest, officer, it won't happen again.' That's what I want is to go through, that wonderful experience of being a dad like my dad was to me."

The card will be up for auction on eBay under the name "Nelkin Baby 2012" the last week of October.